1. Field of the Invention
This invention relates to a web winding method and an apparatus therefor by use of a turret type of winder, and more particularly, to the web winding method and the apparatus for shaping each sheet of paperboard into a cylindrical winding core within the winder instead of using ready-made paper core tubes and winding up a web onto the shaped winding cores.
2. Description of the Related Art
In the winding of a long-length web by the instrumentality of a turret winder, particularly in the case of such a soft plastic film or a thin paper that cannot retain a wind-up roll form, relying on a rigidity of the web itself, it has hitherto been the common practice to wind the web up on winding cores in the form of hollow cylindrical paper tubes or plastic tubes preliminarily manufactured as such.
Where a web is thus wound up on such ready-made winding core tubes as stated above, however, when the web is unwound from wind-up rolls thus produced and used up, these hollow cylindrical winding cores are left behind as useless objects or industrial wastes. Nowadays it becomes unable to discard and dispose of the used core tubes easily even though they are paper tubes. If they will be reused, then a troublesome work and an extra cost might be entailed for collecting, sorting, transportation, or any other control of them.
In the circumstances, with a view to solving the issue of disposal of such wastes of core tubes from an environmental viewpoint, the present inventor has investigated into any alternative winding method and its apparatus. As a result, this invention has been made by developing a new method and an apparatus for winding a web on such easily disposable winding cores that do not produce industrial wastes to be discarded, but are reusable at a low cost. In the course of the development of this invention, a so-called coreless wrap of stretch film has been recently reported. Reportedly, this is a product of a stretchable film wound on a new type of winding core that is made from a sheet of paperboard into a cylinder form instead of using paper tubes as a winding core, but further details on it, such as its manufacturing method and apparatus are not published at all.
In the light of the present state of the art, this invention is designed to propose an independently new efficient web winding method by preparing cylindrical tubes from sheets of paperboard on a winder instead of using conventional ready-made paper tubes as mentioned above and an apparatus for embodying the method. Accordingly, it is a primary object of the invention to conduct a shaping operation of winding cores from sheets of paperboard efficiently and in sequential steps within a winder. Further object is to facilitate the restoration of the winding cores to the original paperboard sheets, even though the winding cores in a hollow cylindrical form remain useless after the web is unwound from resulting wind-up rolls and used up, thereby doing away with the necessity of disposing of the used winding cores as industrial wastes or enabling the reuse of the restored paperboard sheets, if needed.
The present invention for attaining the foregoing objects resides in a method, of winding up a web on winding cores by use of a multiple-spindle turret type of winder, which comprises the sequential steps of rolling and lapping each sheet of paperboard around a winding core shaft and attaching butt joining parts of both edges of the paperboard sheet with a pressure-sensitive adhesive tape, thus shaping paperboard sheets into winding cores; winding up a web onto the shaped winding cores; and subsequently, removing full wind-up rolls wound on the winding cores out of the winder, the aforesaid sequential steps being conducted in conformity with the turning movement (indexing) of the turret within the winder.
The invention resides further in a multiple-spindle turret type of winder for carrying the foregoing method into effect wherein the spindle positions of the turret are allotted to a winding core shaping station, a web winding-up station and a wind-up roll removal station; which winder is equipped, in association with the aforesaid winding core shaping station, with a winding core shaping apparatus for shaping paperboard sheets one by one into winding cores; a web winding-up device; and a removal device of full wind-up rolls out of the winder. In that winder, the winding core shaping apparatus comprises transfer means of transferring paperboard sheets one by one to a tape application bedplate on which to attach and adhere a pressure-sensitive adhesive tape to each paperboard sheet; tape applying means for unreeling the adhesive tape from an adhesive tape roll, cutting it in an adequate length and applying the cut adhesive tape to one edge of each paperboard sheet thus transferred to the tape application bedplate; transfer means of transferring the tape-attached paperboard sheet thus treated to the winding core shaping station where to shape the paperboard sheets into the winding cores; and winding core shaping means for rolling and lapping each sheet of paperboard thus transferred around a winding core shaft positioned at the winding core shaping station of the turret and uniting butt joining parts of both edges of the paperboard sheet together with the adhesive tape; the winding core shaping apparatus, the web winding-up device and the removal device of windup rolls are capable of operating in sequence in association with the winding core shaping station, the web winding-up station and the removal station, respectively in conformity with the turning movement of the turret.
According to this invention, for example, where a three-spindle turret type of winder is used, first, a sheet of paperboard is picked up from a table stacked with paperboard sheets and transferred to the tape application bedplate for an adhesive tape. Concurrently, the adhesive tape is unreeled from an adhesive tape stock roll located in the vicinity of the bedplate and cut in an appropriate length into a strip-like piece, which is in turn applied to the paperboard sheet at its one edge side on the bedplate so that nearly one half part of the adhesive tape piece may cover the one edge of the paperboard sheet. Then the paperboard sheet thus attached at its one edge with the strip-like tape piece is delivered through delivery rollers and transferred to the winding core shaping station located at the upper part of the three-spindle turret winder. At that station, the paperboard sheet is rolled and lapped around a winding core shaft, and resulting butt joining parts of the rolled paperboard sheet are united with the other half part of the adhesive tape piece together and fastened, whereby each shaped cylindrical winding core is ultimately obtained.
When the winding cores are shaped in that shaping station in this way, the turret winder is turned according to a normal operation to move the winding cores to the winding-up station. At the winding-up station a web paid from a stock roll or a preceding step is wound up according to usual procedure. After winding-up, the turret winder is further turned to the wind-up roll removal station where the resulting wind-up rolls are withdrawn.
A series of the actions of shaping into winding cores, winding-up of a web, and removal of wind-up rolls are operated according to a preset drive in the winder, and the taking-up of the web onto winding cores is conducted, while shaping the winding cores, instead of using ready-made winding core tubes.
In the case of a two-spindle turret, the shaping station and the wind-up roll removal station are shared with each other whereas with a four-spindle turret, it is possible to conduct a series of the actions by leaving one spindle position open and making an allowance for functions of the other spindle positions.